The present invention relates to integrated optics beam deflectors and to systems, such as scanners and optical switches, employing such deflectors.
Various types of integrated optics beam deflectors are known in the art. U.S. Pat. No. 5,239,598, the disclosure of which is hereby incorporated by reference, and the references cited therein, as well as the following articles are believed to represent the state of the art:
Katz et al, Phase-locked semiconductor laser array with separate contacts, Appl. Phys. Lett 43, 1983, pp 521-523;
Vasey et al, Spatial optical beam steering with an AlGaAs integrated phased array, Applied Optics, 32, No. 18, 20 June, 1993, pp 3220-3232.
The present invention seeks to provide an improved light beam deflector and systems employing same.
There is thus provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including:
at least one substrate having formed thereon a multiplicity of waveguides, each waveguide receiving light and emitting light, the totality of light emitted by the multiplicity of waveguides producing at least one selectably directable output beam; and
at least one sequential multiplexer applying electrical inputs to the at least one substrate for individually controlling the light emitted by each of the multiplicity of waveguides, thereby governing the orientation of the selectably directable output beam.
Preferably, the at least one sequential multiplexer is a phase controller which controls the phase of the light emitted by each of the multiplicity of waveguides.
Alternatively or additionally, the at least one sequential multiplexer is an intensity controller which controls the intensity of the light emitted by each of the multiplicity of waveguides.
In accordance with a preferred embodiment of the present invention, the at least one substrate includes a plurality of substrates, each having formed thereon a multiplicity of waveguides, each waveguide receiving light and emitting light and wherein the at least one sequential multiplexer applies electrical inputs to the plurality of substrates.
There is also provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including:
a plurality of substrates, each having formed thereon a multiplicity of waveguides, each waveguide receiving light and emitting light, the totality of light emitted by the multiplicity of waveguides producing at least one selectably directable output beam.
Further in accordance with a preferred embodiment of the present invention there is provided a selectably directable optical beam generating device including:
a light source;
at least one substrate having formed thereon a multiplicity of waveguides, each waveguide receiving light from the light source and emitting light, the totality of light emitted by the multiplicity of waveguides producing at least one selectably directable output beam; and
Preferably the light source includes a laser formed on the at least one substrate.
at least one sequential multiplexer applying electrical inputs to the at least one substrate for individually controlling the light emitted by each of the multiplicity of waveguides, thereby governing the orientation of the selectably directable output beam.
Preferably, the at least one sequential multiplexer is a phase controller which controls the phase of the light emitted by each of the multiplicity of waveguides.
Alternatively or additionally, the at least one sequential multiplexer is an intensity controller which controls the intensity of the light emitted by each of the multiplicity of waveguides.
Preferably, the at least one substrate includes a plurality of substrates, each having formed thereon a multiplicity of waveguides, each waveguide receiving light and emitting light and wherein the at least one sequential multiplexer applies electrical inputs to the plurality of substrates.
Additionally in accordance with a preferred embodiment of the present invention there is provided a selectably directable optical beam generating device including:
at least one light source; and
a plurality of substrates, each having formed thereon a multiplicity of waveguides, each waveguide receiving light from the at least one light source and emitting light, the totality of light emitted by the multiplicity of waveguides producing at least one selectably directable output beam.
Still further in accordance with a preferred embodiment of the present invention there is provided a selectably directable optical beam deflecting device including:
at least one substrate having formed thereon a multiplicity of waveguides; and
a microlens array receiving light and coupling the received light to the multiplicity of waveguides.
Additionally in accordance with a preferred embodiment of the present invention there is provided a selectably directable optical beam generating device including:
a light source,
at least one substrate having formed thereon a multiplicity of waveguides; and
a microlens array receiving light from the light source and coupling the received light to the multiplicity of waveguides.
There is also provided in accordance with another preferred embodiment of the present invention a selectably directable optical beam generating device including a light source, at least one substrate having formed thereon a multiplicity of waveguides and a microlens array receiving light from the light source and coupling the received light to the multiplicity of waveguides.
Preferably the selectably directable optical beam generating device provides wavelength division multiplexing.
There is also provided in accordance with another preferred embodiment of the present invention an optical device including at least one substrate having formed thereon a multiplicity of polarization independent, electrically controlled waveguides, and a light receiver directing light into the multiplicity of waveguides.
Further in accordance with a preferred embodiment of the present invention each one of the multiplicity of polarization independent, electrically controlled waveguides includes first and second phase shifting waveguide portions.
Still further in accordance with a preferred embodiment of the present invention the electric fields of different directions are applied to the first and second phase shifting waveguide portions.
Preferably each of the multiplicity of polarization independent electrically controlled waveguides includes first and second phase-shifting waveguide portions of respective first and second lengths having respective first and second electric fields of different directions applied thereto.
Additionally in accordance with a preferred embodiment of the present invention at least one of the multiplicity of polarization independent, electrically controlled waveguides includes first and second phase shifting waveguide portions separated by a quarter-wave plate, whereby light from the first waveguide portion passes through the quarter-wave plate prior to entering the second waveguide portion.
There is also provided in accordance with a preferred embodiment of the present invention an optical device including at least one substrate having formed thereon a multiplicity of electrically controlled waveguides, and a light receiver for directing light into the multiplicity of waveguides, the light receiver including a selectable polarization rotator.
There is also provided in accordance with yet another preferred embodiment of the present invention an optical device including at least one substrate having formed thereon a multiplicity of electrically controlled waveguides, and a polarization rotator for rotating the polarization of light passing through the multiplicity of electrically controlled waveguides by 90 degrees or an odd integer multiple thereof.
Further in accordance with a preferred embodiment of the present invention the polarization rotator operates by generating a magnetic field extending parallel to longitudinal axes of the multiplicity of waveguides.
Still further in a accordance with a preferred embodiment of the present invention the selectable polarization rotator is automatically operative to rotate the polarization so as to provide an optimized light output from the multiplicity of waveguides.
Additionally in accordance with a preferred embodiment of the present invention the selectable polarization rotator is responsive to an output of the multiplicity of waveguides.
Moreover in accordance with a preferred embodiment of the present invention the selectable polarization rotator is responsive to the polarization of an input to the multiplicity of waveguides.
Further in accordance with a preferred embodiment of the present invention and having selectably directable beam deflection functionality. Alternatvely, the selectably directable beam deflection functionality includes directable beam receiving functionality.
Further in accordance with a preferred embodiment of the present invention and the selectably directable functionality is realized by means of phase-shifting.
There is also provided in accordance with yet another preferred embodiment of the present invention an optical device including at least one substrate having formed thereon a multiplicity of electrically controlled waveguides, and a light receiver directing light into the multiplicity of waveguides and including polarization maintaining optical fibers.
There is also provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including at least one substrate having formed thereon a multiplicity of phase-shifting waveguides, and a light receiver directing light into the multiplicity of waveguides, and wherein the at least one substrate includes multiple mutually insulated conductor layers including a multiplicity of conductors, at least some of which are connected to the waveguides by vias.
There is provided in accordance with another preferred embodiment of the present invention a selectably directable optical beam generating device including at least one substrate having formed thereon a multiplicity of waveguides, and a laser monolithically formed on the at least one substrate and providing light to the multiplicity of waveguides.
There is provided in accordance with a preferred embodiment of the present invention an optical device including at least one substrate having formed thereon a multiplicity of waveguides, and a laser monolithically formed on the at least one substrate and providing light to the multiplicity of waveguides, the multiplicity of waveguides and the laser being formed at different regions of identical layers.
There is provided in accordance with yet another preferred embodiment of the present invention a semiconductor laser including an N-doped gallium arsenide substrate, an N-doped aluminum gallium arsenide layer formed over the substrate, an N-doped gallium arsenide layer formed over the N-doped aluminum gallium arsenide layer, a P-doped gallium arsenide layer formed over the N-doped gallium arsenide layer, a P-doped aluminum gallium arsenide layer formed over the P-doped gallium arsenide layer, and a P-doped gallium arsenide layer formed over the P-doped aluminum gallium arsenide layer.
There is provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including at least one substrate having formed thereon a multiplicity of waveguides, and a light receiver coupling light to the multiplicity of waveguides at first ends thereof, and wherein the multiplicity of waveguides are outwardly tapered at the first ends thereof.
There is also provided in accordance with yet another preferred embodiment of the present invention a selectably directable optical beam deflecting device including at least one substrate having formed thereon a multiplicity of waveguides, and a light receiver directing light into the multiplicity of waveguides, the light receiver including a cylindrical lens.
There is also provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including at least one substrate having formed thereon a multiplicity of waveguides, and a light receiver directing light into the multiplicity of waveguides, the light receiver including a multi-mode interference coupler.
There is also provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including at least one substrate having formed thereon a multiplicity of waveguides, and a light receiver directing light into the multiplicity of waveguides, the light receiver including a planar wave guide.
Further in accordance with a preferred embodiment of the present invention the multiplicity of waveguides have first ends which abut the planar waveguide, the first ends being tapered outwardly.
Still further in accordance with a preferred embodiment of the present invention the multi-mode interference coupler includes a light receiving waveguide. Preferably the light receiving waveguide includes a light receiving end which is outwardly tapered.
Additionally in a accordance with a preferred embodiment of the present invention the light receiving waveguide includes an electro-absorption modulator.
Moreover in accordance with a preferred embodiment of the present invention the electro-absorption modulator receives a modulating input from a light detector monolithically formed therewith on the at least one substrate.
Additionally or alternatively the multiplicity of waveguides is controllable so as to selectably provide multiple selectably directed output beams.
There is also provided in accordance with a preferred embodiment of the present invention a selectably directable optical beam deflecting device including at least one substrate having formed thereon a multiplicity of waveguides, and a light receiver directing light into the multiplicity of waveguides, and wherein the multiplicity of waveguides is controllable so as to selectably provide multiple selectably directed output beams.
Additionally or alternatively the optical device also includes a waveguide filter including a necked waveguide having a relatively broad input end which receives light and allows propagation of multi-mode light waves therethrough, a narrowed neck portion at which higher modes radiate outside the waveguide and only the modes which can propagate therethrough pass therethrough, and a relatively broad output end.
There is also provided in accordance with a preferred embodiment of the present invention a waveguide filter including a necked waveguide having a relatively broad input end which receives light and allows propagation of multi-mode light waves therethrough, a narrowed neck portion at which higher modes radiate outside the waveguide and only the modes which can propagate therethrough pass therethrough, and a relatively broad output end.
Preferably the optical device is implemented on gallium arsenide.
There is also provided in accordance with a preferred embodiment of the present invention an optical switch including a monolithic plurality of selectably directable optical beam deflecting devices, a plurality of optical beam receiving devices.
There is also provided in accordance with yet another preferred embodiment of the present invention an optical switch including a plurality of monolithic pluralities of selectably directable optical beam deflecting devices, a plurality of optical beam receiving devices.
Further in accordance with a preferred embodiment of the present invention the plurality of monolithic pluralities of beam deflecting devices are arranged generally parallel to one another along an axis perpendicular to a plane in which selectable deflection of a light beam is produced thereby.
Still further in accordance with a preferred embodiment of the present invention the plurality of monolithic pluralities of beam deflecting devices are arranged generally distributed along a curve extending in a plane perpendicular to a plane in which selectable deflection of a light beam is produced thereby.
There is also provided in accordance with yet another preferred embodiment of the present invention an optical switch including a plurality of selectably directable optical beam deflecting devices, each including at least one substrate having formed thereon a multiplicity of waveguides, and a plurality of optical beam receiving devices.
Further in accordance with a preferred embodiment of the present invention each of the plurality of optical beam receiving devices includes an optical fiber. Preferably the optical fiber has a numerical aperture of less than 0.3.
Additionally in accordance with a preferred embodiment of the present invention the selectably directable optical beam deflecting devices each include at least one substrate having formed thereon a multiplicity of waveguides.
There is also provided in accordance with a preferred embodiment of the present invention an optical switch including a plurality of optical beam emitting devices and a monolithic plurality of selectably directable optical beam receiving devices. Preferably the optical beam receiving devices are selectably directable.
There is also provided in accordance with a preferred embodiment of the present invention an optical switch including a plurality of optical beam emitting devices and a plurality of monolithic pluralities of selectably directable optical beam receiving devices.
Further in accordance with a preferred embodiment of the present invention the plurality of monolithic pluralities of beam receiving devices are arranged generally parallel to one another along an axis perpendicular to a plane in which selectable deflection of a light beam is produced thereby. Alternatively the plurality of monolithic pluralities of beam receiving devices are arranged generally distributed along a curve extending in a plane perpendicular to a plane in which selectable deflection of a light beam is produced thereby.
Still further in accordance with a preferred embodiment of the present invention the selectable directable optical beam receiving devices each include at least one substrate having formed thereon a multiplicity of waveguides.
There is also provided in accordance with a preferred embodiment of the present invention an optical switch including a plurality of optical beam emitting devices, and a plurality of selectably directable optical beam receiving devices, each including at least one substrate having formed thereon a multiplicity of waveguides.
Additionally in accordance with a preferred embodiment of the present invention both the optical beam emitting devices and the optical beam receiving devices are selectably directable.
Moreover in accordance with a preferred embodiment of the present invention and including a light input coupler to the plurality of optical beam devices and a cylindrical lens light output coupler receiving light from the plurality of optical beam devices. Preferably the cylindrical lens light output coupler includes a plurality of cylindrical lenses, each associated with an optical beam device. Alternatively the cylindrical lens light output coupler includes a single cylindrical lens associated with a plurality of optical beam devices.
Additionally in accordance with a preferred embodiment of the present invention and including a light input coupler to the plurality of optical beam devices which includes at least one cylindrical lens. Preferably the light input coupler to the plurality of optical beam devices includes at least one cylindrical lens.
Moreover in accordance with a preferred embodiment of the present invention the at least one cylindrical lens includes a plurality of cylindrical lenses, each associated with an optical beam device.
Still further in accordance with a preferred embodiment of the present invention the at least one cylindrical lens includes a single cylindrical lens associated with a plurality of optical beam devices.
Further in accordance with a preferred embodiment of the present invention the light input coupler also includes a multiplicity of microlenses fixed with respect to the at least one cylindrical lens, each of the multiplicity of microlenses directing light into a single beam transmitting device.
Preferably the multiplicity of microlenses includes focusing microlenses. Alternatively the multiplicity of microlenses includes collimating microlenses.
There is also provided in accordance with a preferred embodiment of the present invention an active optical beam transmission device including at least one substrate having formed thereon a multiple layer integrated electronic circuit, and a multiplicity of electrically controlled waveguides.
Further in accordance with a preferred embodiment of the present invention the waveguides emit a selectably directable beam of light. Alternatively or additionally the waveguides selectably receive a beam of light.
Still further in accordance with a preferred embodiment of the present invention the multiplicity of waveguides are operative simultaneously to deflect a plurality of optical beams.
Preferably overlying the waveguides, a multiplicity of electrical contacts, each contact providing an electrical connection to at least one of the multiplicity of electrically controlled waveguides.
There is also provided in accordance with a preferred embodiment of the present invention an active optical beam transmission device including at least one substrate having formed thereon a plurality of waveguide assemblies, each including a multiplicity of electrically controlled waveguides, and overlying each of the waveguide assemblies, a multiplicity of electrical contacts, each contact providing an electrical connection to at least one of the multiplicity of electrically controlled waveguides in the assembly.
There is also provided in accordance with a preferred embodiment of the present invention a monolithic optical light modulator including a substrate having formed monolithically thereon an electro-absorption modulator, and a light detector providing a modulating output to the electro-absorption modulator.
There is also provided in accordance with a preferred embodiment of the present invention an optical waveguide-lens including at least one substrate having formed thereon a multiplicity of electrically controlled, phase-shifting waveguides, and an electrical control signal source providing electrical signals to the multiplicity of waveguides to cause them to have a desired lens functionality.
Additionally the optical devies described hereinabove may also include an electrical control signal source providing electrical signals to the multiplicity of waveguides to cause them to have a desired lens functionality. Furthermore the optical devices may also include a feedback connection between the optical beam receiving devices and the optical beam deflecting devices.
Still further in accordance with a preferred embodiment of the present invention the optical beam receiving devices are configured to receive light over a region sufficiently large such that wavelength dependencies of the deflectors do not substantially affect the amount of light sensed by the receiving devices.
There is also provided in accordance with a preferred embodiment of the present invention an optical switch including a plurality of selectably directable optical beam deflecting devices, a plurality of optical beam receiving devices, and wherein the plurality of selectably directable optical beam deflecting devices and the plurality of optical beam receiving devices are monolithically formed on the same substrate.
Further in accordance with a preferred embodiment of the present invention the plurality of selectably directable optical beam deflecting devices and the plurality of optical beam receiving devices are monolithically formed on the same substrate.
There is also provided in accordance with a preferred embodiment of the present invention a method of forming a monolithic structure having electrical contacts including the steps of configuring regions on a wafer such that upper and lower surfaces are defined thereon, coating the upper and lower surfaces with metal by evaporation in a direction generally perpendicular to the upper and lower surfaces, the direction being selected with respect to interconnecting surfaces which interconnect the upper and lower surfaces such that metal is not substantially coated onto the interconnecting surfaces, whereby electrical connections between the upper and lower surfaces via the interconnecting surfaces are not formed by the metal coating.
Further in accordance with a preferred embodiment of the present invention the monolithic structure includes a waveguide device.
There is also provided in accordance with yet another preferred embodiment of the present invention a method for aligning a waveguide device including providing a waveguide having light emitting capability, and operating the waveguide to emit light during alignment thereof.
There is also provided in accordance with a preferred embodiment of the present invention an optical switch including a plurality of ports, an optical crossbar assembly, and a plurality of information carrying optical fibers interconnecting the plurality of ports with inputs to the optical crossbar assembly, the information carrying optical fibers including polarization maintaining fibers.
There is also provided in accordance with yet another preferred embodiment of the present invention an optical switch including a plurality of ports, an optical crossbar assembly, and a plurality of information carrying optical fibers interconnecting the plurality of ports with inputs to the optical crossbar assembly, the plurality of ports each having an input and output which are clock synchronized.
Additionally in a accordance with a preferred embodiment of the present invention the plurality of ports are clock synchronized among themselves.